Big animals can survive reduced-impact logging — if done right

Employing camera traps to survey Amazonian mammals in Guyana, researchers found that large mammals and birds did not see a lower population of target species in reduced-impact logging areas as compared to unlogged areas. For some species, like jaguars and pumas, population numbers actually rose.

The research was conducted in an unusually managed swath of forest: Iwokrama. Spreading over nearly 400,000 hectares (close to 990,000 acres) – an area a little smaller than Rhode Island – Iwokrama Forest is managed by the not-for-profit Iwokrama organization and 16 local Makushi communities.

Looking at 17 key species in the area – including 15 mammals and two large birds – the researchers found that populations didn’t change much between logged and unlogged areas, a sign that Iwokrama’s logging regime is not disturbing the area’s larger taxa.

Reduced-impact logging doesn’t need to be a death knell for a region’s big animals, according to a new study in Biotropica — but only if hunting is well-regulated.

Employing camera traps to survey Amazonian animals in Guyana, researchers found that large mammals and birds did not see a lower population of target species in reduced-impact logging areas as compared to unlogged areas. For some species, like jaguars and pumas, population numbers actually rose.

The research was conducted in an unusually managed swath of forest: Iwokrama.

“Iwokrama’s management is fully integrated with the indigenous people who have used these forests for thousands of years and are now socially and financially invested in the Iwokrama project,” explained lead author, Anand Roopsind, a PhD Candidate with the University of Florida.

Spreading over nearly 400,000 hectares (close to 990,000 acres) — an area a little smaller than Rhode Island — Iwokrama Forest is managed by the not-for-profit Iwokrama organization and 16 local Makushi communities through the North Rupununi District Development Board with support from the Guyanese government and the private sector. The organization funds itself in part via ecotourism and reduced-impact logging. Local indigenous people are allowed to hunt for subsistence in Iwokrama Forest, but all hunting by outsiders or for commercial use is strictly prohibited.

Iwokrama’s reduced-impact logging program, which received FSC-certification in 2016, is stringent compared to industry norms. Iwokrama logs under a 60-year-cycle (a long cycle for the tropics) and on average only cuts six trees per hectare. Other regulations include a thorough inventory before logging occurs, chopping lianas on target trees so they don’t pull down other trees when they are felled, making certain a tree falls at a clear path, and planning and managing road building.

“Iwokrama must first comply with its own internal regulations even before FSC certification,” said Roopsind. “In contrast, most logging companies are driven by maximizing profits, even though they comply with FSC standards.”

The differences were clear. Looking at 17 key species in the area — including 15 mammals and two large birds – the researchers found that populations didn’t change much between logged and unlogged areas, a sign that Iwokrama’s logging regime is not disturbing the area’s larger taxa. Indeed, top predators like jaguar and puma appear to prefer the logged areas.

Roopsind said that large carnivores often use logged areas because it’s easier to get around and “new vegetative growth” that arises after felling may attract their prey.

“Camera traps may have an easier time detecting animals in logging areas,” he added. This means that since logging areas have clear trails and roads, it’s sometimes easier to pick up more animals on camera trap there than in unlogged areas. Scientists build such factors into their models, but it can still skew results.

One of the most important lessons from the study, according to its authors, is how Iwokrama deals with hunting. Usually, logging areas in the tropics — even those checked off by the FSC and other groups as ‘sustainable’ — see a dramatic rise in hunting, either done by logging employees or by local people who gain access to the area via new roads. But Iwokrama has managed to keep its hunting strictly enforced by indigenous people, who are aided by the forest’s remoteness and several checkpoints on the main road into the site.

“The importance of Iwokrama’s control of poaching should not be underestimated,” said co-author, Jack Putz, a professor at the University of Florida.

The researchers note in their paper that maintaining large animals is important for timber resources, given that large birds and mammals disperse tropical tree seeds through the forest.

“If hunting is managed, wildlife populations may be able to persist under reduced-impact logging,” Roopsind said. “This result is good news for tropical forests, because it suggests that allowing some logging could be a way to provide economic development while conserving biodiversity.”

Indeed, the researchers found that hunting — not logging — may be the biggest threat to wildlife in Iwokrama, a result that echoes recent research in Southeast Asia and the global tropics. Such research hints that hunting may be a larger threat to vertebrates even than habitat loss. In known hunting areas of Iwokrama, scientists captured fewer animals on film. But they caution that these lower populations may be replaced by animals coming in from other areas and finding less competition.

“Repeated kills at specific sites likely reflect both traditional hunter knowledge and locations favored by their preferred bush meat species,” the researchers write in the paper. In other words, hunting areas may be population sinks that are consistently filled in by surrounding areas.

Roopsind said that what’s needed now are “long-term data on wildlife populations to assess what yields of hunting offtake are sustainable.”

Still, Iwokrama’s forests and wildlife populations overall look good even with reduced-impact logging and subsistence hunting, according to Roopsind. The key to Iwokrama’s program is that it has “invested human and financial capital into building the capacity of local communities,” he said.

“To spread the lessons of Iwokrama to other forests, the international community needs to provide financial rewards like payment for ecosystem services, premiums and preferential market access as incentives for high forestry and social responsibility standards,” Roopsind added. “Otherwise these lessons will be hard for timber concessions to adopt if they see the investment in training, for responsible forestry as a profit-reducing activity in the face of highly unregulated timber production.”